Welding is best. U can calmp temporariliy, but it needs to be welded if you wheel it you will rip it off. I clamped my new glasspack on at home then had it welded and a tailpipe bent later at a shop for only $60. A buddy of mine tore his clamped one off three times in just over a year. He had one trip of 80 miles home running nothing but tha cat. Rather unpleasant.
Also if you wheel it, use that as an oportunity to move any piping out of harms way if you can. I ran my tailpipe straight along side the tank skid adn ended it before the back of the tank so hopefully it can't get smashed or hung up on a rock.